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Chen LC, Li MC, Chen KR, Cheng YJ, Wu XY, Chen SA, Youh MJ, Kuo CC, Lin YX, Lin CY, Wang CF, Huang CF, Lin SY, Wang WH, Chen YH, Yu ML, Thitithanyanont A, Wang SF, Su LC. Facile and Unplugged Surface Plasmon Resonance Biosensor with NIR-Emitting Perovskite Nanocomposites for Fast Detection of SARS-CoV-2. Anal Chem 2023; 95:7186-7194. [PMID: 37103881 PMCID: PMC10152400 DOI: 10.1021/acs.analchem.2c05661] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/19/2022] [Accepted: 04/11/2023] [Indexed: 04/28/2023]
Abstract
The emergence of the coronavirus disease 2019 (COVID-19) pandemic prompted researchers to develop portable biosensing platforms, anticipating to detect the analyte in a label-free, direct, and simple manner, for deploying on site to prevent the spread of the infectious disease. Herein, we developed a facile wavelength-based SPR sensor built with the aid of a 3D printing technology and synthesized air-stable NIR-emitting perovskite nanocomposites as the light source. The simple synthesis processes for the perovskite quantum dots enabled low-cost and large-area production and good emission stability. The integration of the two technologies enabled the proposed SPR sensor to exhibit the characteristics of lightweight, compactness, and being without a plug, just fitting the requirements of on-site detection. Experimentally, the detection limit of the proposed NIR SPR biosensor for refractive index change reached the 10-6 RIU level, comparable with that of state-of-the-art portable SPR sensors. In addition, the bio-applicability of the platform was validated by incorporating a homemade high-affinity polyclonal antibody toward the SARS-CoV-2 spike protein. The results demonstrated that the proposed system was capable of discriminating between clinical swab samples collected from COVID-19 patients and healthy subjects because the used polyclonal antibody exhibited high specificity against SARS-CoV-2. Most importantly, the whole measurement process not only took less than 15 min but also needed no complex procedures or multiple reagents. We believe that the findings disclosed in this work can open an avenue in the field of on-site detection for highly pathogenic viruses.
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Affiliation(s)
- Lung-Chien Chen
- Department of Electro-Optical Engineering,
National Taipei University of Technology, Taipei 10608,
Taiwan
| | - Meng-Chi Li
- Thin Film Technology Center, National
Central University, Taoyuan 32001, Taiwan
- Optical Sciences Center, National Central
University, Taoyuan 32001, Taiwan
| | - Kai-Ren Chen
- Department of Optics and Photonics,
National Central University, Taoyuan 32001,
Taiwan
| | - Yu-Jui Cheng
- Department of Electronic Engineering,
Ming Chi University of Technology, New Taipei City 24301,
Taiwan
| | - Xun-Ying Wu
- Department of Mechanical Engineering, Ming Chi
University of Technology, New Taipei City 24301,
Taiwan
| | - Sih-An Chen
- Department of Electro-Optical Engineering,
National Taipei University of Technology, Taipei 10608,
Taiwan
| | - Meng-Jey Youh
- Department of Mechanical Engineering, Ming Chi
University of Technology, New Taipei City 24301,
Taiwan
| | - Chien-Cheng Kuo
- Thin Film Technology Center, National
Central University, Taoyuan 32001, Taiwan
- Department of Optics and Photonics,
National Central University, Taoyuan 32001,
Taiwan
| | - Yu-Xen Lin
- TeraOptics Corporation,
Taoyuan 32472, Taiwan
| | - Chih-Yen Lin
- Center for Tropical Medicine and Infectious Disease
Research, Kaohsiung Medical University, Kaohsiung 80708,
Taiwan
- Department of Medical Laboratory Science and
Biotechnology, Kaohsiung Medical University, Kaohsiung 80708,
Taiwan
| | - Chu-Feng Wang
- Clinical Microbiology Laboratory, Department of
Laboratory Medicine, Kaohsiung Medical University Hospital, Kaohsiung Medical
University, Kaohsiung 80708, Taiwan
| | - Chung-Feng Huang
- Hepatobiliary Division, Department of
Internal Medicine, Kaohsiung Medical University Hospital, Kaohsiung Medical
University, Kaohsiung 80708, Taiwan
- Ph.D. Program in Translational Medicine,
College of Medicine, Kaohsiung Medical University, Kaohsiung, and Academia
Sinica, Kaohsiung 80708, Taiwan
- Faculty of Internal Medicine and Hepatitis
Research Center, College of Medicine, and Center for Cohort Study, Kaohsiung
Medical University, Kaohsiung 80708, Taiwan
| | - Shang-Yi Lin
- Clinical Microbiology Laboratory, Department of
Laboratory Medicine, Kaohsiung Medical University Hospital, Kaohsiung Medical
University, Kaohsiung 80708, Taiwan
- Division of Infectious Disease, Department of
Internal Medicine, Kaohsiung Medical University Hospital, Kaohsiung Medical
University, Kaohsiung 80708, Taiwan
| | - Wen-Hung Wang
- School of Medicine, College of Medicine,
National Sun Yat-Sen University, Kaohsiung 80424,
Taiwan
| | - Yen-Hsu Chen
- Center for Tropical Medicine and Infectious Disease
Research, Kaohsiung Medical University, Kaohsiung 80708,
Taiwan
- Division of Infectious Disease, Department of
Internal Medicine, Kaohsiung Medical University Hospital, Kaohsiung Medical
University, Kaohsiung 80708, Taiwan
- School of Medicine, College of Medicine,
National Sun Yat-Sen University, Kaohsiung 80424,
Taiwan
| | - Ming-Lung Yu
- Hepatobiliary Division, Department of
Internal Medicine, Kaohsiung Medical University Hospital, Kaohsiung Medical
University, Kaohsiung 80708, Taiwan
- School of Medicine, College of Medicine,
National Sun Yat-Sen University, Kaohsiung 80424,
Taiwan
| | - Arunee Thitithanyanont
- Department of Microbiology, Faculty of Science,
Mahidol University, Bangkok 10400,
Thailand
| | - Sheng-Fan Wang
- Center for Tropical Medicine and Infectious Disease
Research, Kaohsiung Medical University, Kaohsiung 80708,
Taiwan
- Department of Medical Laboratory Science and
Biotechnology, Kaohsiung Medical University, Kaohsiung 80708,
Taiwan
- Department of Medical Research,
Kaohsiung Medical University Hospital, Kaohsiung Medical
University, Kaohsiung 80708, Taiwan
| | - Li-Chen Su
- General Education Center, Ming
Chi University of Technology, New Taipei City 24301,
Taiwan
- Organic Electronics Research Center,
Ming Chi University of Technology, New Taipei City 24301,
Taiwan
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Chang CP, Shih CH, You JL, Youh MJ, Liu YM, Ger MD. Preparation and Ballistic Performance of a Multi-Layer Armor System Composed of Kevlar/Polyurea Composites and Shear Thickening Fluid (STF)-Filled Paper Honeycomb Panels. Polymers (Basel) 2021; 13:3080. [PMID: 34577980 PMCID: PMC8467087 DOI: 10.3390/polym13183080] [Citation(s) in RCA: 4] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/15/2021] [Revised: 09/04/2021] [Accepted: 09/06/2021] [Indexed: 11/24/2022] Open
Abstract
In this study, the ballistic performance of armors composed of a polyurea elastomer/Kevlar fabric composite and a shear thickening fluid (STF) structure was investigated. The polyurea used was a reaction product of aromatic diphenylmethane isocyanate (A agent) and amine-terminated polyether resin (B agent). The A and B agents were diluted, mixed and brushed onto Kevlar fabric. After the reaction of A and B agents was complete, the polyurea/Kevlar composite was formed. STF structure was prepared through pouring the STF into a honeycomb paper panel. The ballistic tests were conducted with reference to NIJ 0101.06 Ballistic Test Specification Class II and Class IIIA, using 9 mm FMJ and 44 magnum bullets. The ballistic test results reveal that polyurea/Kevlar fabric composites offer better impact resistance than conventional Kevlar fabrics and a 2 mm STF structure could replace approximately 10 layers of Kevlar in a ballistic resistant layer. Our results also showed that a high-strength composite laminate using the best polyurea/Kevlar plates combined with the STF structure was more than 17% lighter and thinner than the conventional Kevlar laminate, indicating that the high-strength protective material developed in this study is superior to the traditional protective materials.
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Affiliation(s)
- Chang-Pin Chang
- Department of Chemical & Materials Engineering, Chung Cheng Institute of Technology, National Defense University, Taoyuan 335, Taiwan; (C.-P.C.); (J.-L.Y.); (Y.-M.L.)
- System Engineering and Technology Program, National Chiao Tung University, Hsinchu 300, Taiwan
| | - Cheng-Hung Shih
- Graduate School of Defense Science, Chung Cheng Institute of Technology, National Defense University, Taoyuan 335, Taiwan;
| | - Jhu-Lin You
- Department of Chemical & Materials Engineering, Chung Cheng Institute of Technology, National Defense University, Taoyuan 335, Taiwan; (C.-P.C.); (J.-L.Y.); (Y.-M.L.)
- System Engineering and Technology Program, National Chiao Tung University, Hsinchu 300, Taiwan
| | - Meng-Jey Youh
- Department of Mechanical Engineering, Ming Chi University of Technology, Taishan, New Taipei City 243, Taiwan
| | - Yih-Ming Liu
- Department of Chemical & Materials Engineering, Chung Cheng Institute of Technology, National Defense University, Taoyuan 335, Taiwan; (C.-P.C.); (J.-L.Y.); (Y.-M.L.)
- System Engineering and Technology Program, National Chiao Tung University, Hsinchu 300, Taiwan
| | - Ming-Der Ger
- Department of Chemical & Materials Engineering, Chung Cheng Institute of Technology, National Defense University, Taoyuan 335, Taiwan; (C.-P.C.); (J.-L.Y.); (Y.-M.L.)
- System Engineering and Technology Program, National Chiao Tung University, Hsinchu 300, Taiwan
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Youh MJ, Chung MC, Tai HC, Chen CY, Li YY. Fabrication of carbon quantum dots via ball milling and their application to bioimaging. Mendeleev Communications 2021. [DOI: 10.1016/j.mencom.2021.09.018] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 10/19/2022]
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Youh MJ, Huang YR, Peng CH, Lin MH, Chen TY, Chen CY, Liu YM, Pu NW, Liu BY, Chou CH, Hou KH, Ger MD. Using Graphene-Based Composite Materials to Boost Anti-Corrosion and Infrared-Stealth Performance of Epoxy Coatings. Nanomaterials (Basel) 2021; 11:nano11061603. [PMID: 34207195 PMCID: PMC8234136 DOI: 10.3390/nano11061603] [Citation(s) in RCA: 4] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 05/09/2021] [Revised: 06/10/2021] [Accepted: 06/15/2021] [Indexed: 01/10/2023]
Abstract
Corrosion prevention and infrared (IR) stealth are conflicting goals. While graphene nanosheets (GN) provide an excellent physical barrier against corrosive agent diffusion, thus lowering the permeability of anti-corrosion coatings, they have the side-effect of decreasing IR stealth. In this work, the anti-corrosion properties of 100-μm-thick composite epoxy coatings with various concentrations (0.01–1 wt.%) of GN fillers thermally reduced at different temperatures (300 °C, 700 °C, 1100 °C) are first compared. The performance was characterized by potentiodynamic polarization scanning, electrochemical impedance spectroscopy, water contact angle and salt spray tests. The corrosion resistance for coatings was found to be optimum at a very low filler concentration (0.05 wt.%). The corrosion current density was 4.57 × 10−11 A/cm2 for GN reduced at 1100 °C, showing no degradation after 500 h of salt-spray testing: a significant improvement over the anti-corrosion behavior of epoxy coatings. Further, to suppress the high IR thermal signature of GN and epoxy, Al was added to the optimized composite at different concentrations. The increased IR emissivity due to GN was not only eliminated but was in fact reduced relative to the pure epoxy. These optimized coatings of Al-GN-epoxy not only exhibited greatly reduced IR emissivity but also showed no sign of corrosion after 500 h of salt spray test.
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Affiliation(s)
- Meng-Jey Youh
- Department of Mechanical Engineering, Ming Chi University of Technology, Taishan, New Taipei City 243, Taiwan;
| | - Yu-Ren Huang
- Department of Applied Science, R.O.C. Naval Academy, Zuoying, Kaohsiung 813, Taiwan;
| | - Cheng-Hsiung Peng
- Department of Chemical and Materials Engineering, Minghsin University of Science and Technology, Xinfeng, Hsinchu 304, Taiwan;
| | - Ming-Hsien Lin
- Department of Chemical & Materials Engineering, Chung Cheng Institute of Technology, National Defense University, Dasi, Taoyuan 335, Taiwan; (M.-H.L.); (T.-Y.C.); (Y.-M.L.)
| | - Ting-Yu Chen
- Department of Chemical & Materials Engineering, Chung Cheng Institute of Technology, National Defense University, Dasi, Taoyuan 335, Taiwan; (M.-H.L.); (T.-Y.C.); (Y.-M.L.)
| | - Chun-Yu Chen
- Department of Electrical Engineering, Yuan Ze University, Zhongli, Taoyuan 320, Taiwan; (C.-Y.C.); (B.-Y.L.); (C.-H.C.); (K.-H.H.)
- Chemical System Research Division, National Chung Shan Institute of Science and Technology, Longtan, Taoyuan 325, Taiwan
| | - Yih-Ming Liu
- Department of Chemical & Materials Engineering, Chung Cheng Institute of Technology, National Defense University, Dasi, Taoyuan 335, Taiwan; (M.-H.L.); (T.-Y.C.); (Y.-M.L.)
| | - Nen-Wen Pu
- Department of Electrical Engineering, Yuan Ze University, Zhongli, Taoyuan 320, Taiwan; (C.-Y.C.); (B.-Y.L.); (C.-H.C.); (K.-H.H.)
- Correspondence: (N.-W.P.); (M.-D.G.); Fax: +886-3-3808906 (M.-D.G.)
| | - Bo-Yi Liu
- Department of Electrical Engineering, Yuan Ze University, Zhongli, Taoyuan 320, Taiwan; (C.-Y.C.); (B.-Y.L.); (C.-H.C.); (K.-H.H.)
| | - Chen-Han Chou
- Department of Electrical Engineering, Yuan Ze University, Zhongli, Taoyuan 320, Taiwan; (C.-Y.C.); (B.-Y.L.); (C.-H.C.); (K.-H.H.)
| | - Kai-Hsiang Hou
- Department of Electrical Engineering, Yuan Ze University, Zhongli, Taoyuan 320, Taiwan; (C.-Y.C.); (B.-Y.L.); (C.-H.C.); (K.-H.H.)
| | - Ming-Der Ger
- Department of Chemical & Materials Engineering, Chung Cheng Institute of Technology, National Defense University, Dasi, Taoyuan 335, Taiwan; (M.-H.L.); (T.-Y.C.); (Y.-M.L.)
- Correspondence: (N.-W.P.); (M.-D.G.); Fax: +886-3-3808906 (M.-D.G.)
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Youh MJ, Jiang MY, Chung MC, Tai HC, Li YY. Formation of graphene quantum dots by ball-milling technique using carbon nanocapsules and sodium carbonate. INORG CHEM COMMUN 2020. [DOI: 10.1016/j.inoche.2020.108061] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/26/2022]
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Huang JB, Patra J, Lin MH, Ger MD, Liu YM, Pu NW, Hsieh CT, Youh MJ, Dong QF, Chang JK. A Holey Graphene Additive for Boosting Performance of Electric Double-Layer Supercapacitors. Polymers (Basel) 2020; 12:polym12040765. [PMID: 32244627 PMCID: PMC7240531 DOI: 10.3390/polym12040765] [Citation(s) in RCA: 4] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/27/2020] [Revised: 03/25/2020] [Accepted: 03/27/2020] [Indexed: 11/16/2022] Open
Abstract
We demonstrate a facile and effective method, which is low-cost and easy to scale up, to fabricate holey graphene nanosheets (HGNSs) via ultrafast heating during synthesis. Various heating temperatures are used to modify the material properties of HGNSs. First, we use HGNSs as the electrode active materials for electric double-layer capacitors (EDLCs). A synthesis temperature of 900 °C seems to be optimal, i.e., the conductivity and adhesion of HGNSs reach a compromise. The gravimetric capacitance of this HGNS sample (namely HGNS-900) is 56 F·g−1. However, the volumetric capacitance is low, which hinders its practical application. Secondly, we incorporate activated carbon (AC) into HGNS-900 to make a composite EDLC material. The effect of the AC:HGNS-900 ratio on the capacitance, high-rate performance, and cycling stability are systematically investigated. With a proper amount of HGNS-900, both the electrode gravimetric and volumetric capacitances at high rate charging/discharging are clearly higher than those of plain AC electrodes. The AC/HGNS-900 composite is a promising electrode material for nonaqueous EDLC applications.
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Affiliation(s)
- Jun-Bin Huang
- Department of Chemical and Materials Engineering, Chung Cheng Institute of Technology, National Defense University, 1000 Xingfeng Road, Taoyuan 335, Taiwan; (J.-B.H.); (M.-H.L.); (Y.-M.L.)
| | - Jagabandhu Patra
- Hierarchical Green-Energy Materials (Hi-GEM) Research Center, National Cheng Kung University, 1 University Road, Tainan 70101, Taiwan;
- Department of Materials Science and Engineering, National Chiao Tung University, 1001 University Road, Hsinchu 30010, Taiwan
| | - Ming-Hsien Lin
- Department of Chemical and Materials Engineering, Chung Cheng Institute of Technology, National Defense University, 1000 Xingfeng Road, Taoyuan 335, Taiwan; (J.-B.H.); (M.-H.L.); (Y.-M.L.)
| | - Ming-Der Ger
- Department of Chemical and Materials Engineering, Chung Cheng Institute of Technology, National Defense University, 1000 Xingfeng Road, Taoyuan 335, Taiwan; (J.-B.H.); (M.-H.L.); (Y.-M.L.)
- Correspondence: (M.-D.G.); (N.-W.P.); (J.-K.C.); Tel.: +886-3-5712121 (ext. 55320) (J.-K.C.)
| | - Yih-Ming Liu
- Department of Chemical and Materials Engineering, Chung Cheng Institute of Technology, National Defense University, 1000 Xingfeng Road, Taoyuan 335, Taiwan; (J.-B.H.); (M.-H.L.); (Y.-M.L.)
| | - Nen-Wen Pu
- Department of Photonics Engineering, Yuan Ze University, 135 Yuan-Tung Road, Taoyuan 32003, Taiwan
- Correspondence: (M.-D.G.); (N.-W.P.); (J.-K.C.); Tel.: +886-3-5712121 (ext. 55320) (J.-K.C.)
| | - Chien-Te Hsieh
- Department of Mechanical, Aerospace, and Biomedical Engineering, University of Tennessee, Knoxville, TN 37996, USA;
| | - Meng-Jey Youh
- Department of Mechanical Engineering, Ming Chi University of Technology, 84 Gongzhuan Road, Taishan District, New Taipei City 243, Taiwan;
| | - Quan-Feng Dong
- State Key Laboratory for Physical Chemistry of Solid Surfaces, Department of Chemistry, Xiamen University, Xiamen 361005, China;
| | - Jeng-Kuei Chang
- Hierarchical Green-Energy Materials (Hi-GEM) Research Center, National Cheng Kung University, 1 University Road, Tainan 70101, Taiwan;
- Department of Materials Science and Engineering, National Chiao Tung University, 1001 University Road, Hsinchu 30010, Taiwan
- Correspondence: (M.-D.G.); (N.-W.P.); (J.-K.C.); Tel.: +886-3-5712121 (ext. 55320) (J.-K.C.)
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Pu NW, Chou YP, Liu YM, Ger MD, Hou KH, Youh MJ. Helical-Cathode Bulb-Shaped Field Emission Lamps Using Carbon Nanocoil Electron Emitters. J Nanosci Nanotechnol 2017; 17:1076-1082. [PMID: 29676552 DOI: 10.1166/jnn.2017.12707] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/08/2023]
Abstract
Bulb-shaped field emission lamps (FELs) with a helical cathode filament were simulated and fabricated in this research. The light bulbs comprised a helical stainless steel filament cathode grown with carbon nano-coils (CNCs) and an Al anode deposited on the bottom hemisphere of a 60-mm-diameter glass bulb. White light was generated when the field-emitted electrons bombarded a layer of three-color phosphor coated on the anode. A numerical simulation model for the helical-cathode FELs was constructed, and the field emission (FE) performance was carefully studied. Due to the screening effect, the electric field strength as well as the FE current density on the inner side of the helix dramatically decreased with decreasing helical pitch. Real FELs using cathodes with various helical radii and pitches were fabricated and their FE currents were measured. The theoretical and experimental results were in good agreement. A maximum total FE current was found at a pitch of 16 mm (helical radius = 2 mm), where the optimum trade-off between a large total surface area and a small screening effect was obtained. The optimized FEL showed a total luminous flux of about 220 lm at an applied voltage of 8 kV and a color rendering index of 94. Compared to a straight filament cathode, a helical cathode offered a higher total FE current or, alternatively, a lower current density and a longer cathode life, if we fix the total current by using a lower voltage.
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Nian YY, Youh MJ, Chang CP, Chen YC, Ger MD. Preparation of styrene-γ-methacryloxypropyltrimethoxysilane/Pd nanoparticles as ink for ink-jet printing technology and electroless nickel plating on glass. J Taiwan Inst Chem Eng 2016. [DOI: 10.1016/j.jtice.2016.08.034] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/21/2022]
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Pu NW, Youh MJ, Chung KJ, Liu YM, Ger MD. Field Emission Lamps Prepared with Dip-Coated and Nickel Electroless Plated Carbon Nanotube Cathodes. J Nanosci Nanotechnol 2015; 15:5093-5098. [PMID: 26373085 DOI: 10.1166/jnn.2015.9258] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [What about the content of this article? (0)] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/05/2023]
Abstract
Fabrication and efficiency enhancement of tubal field emission lamps (FELs) using multi-walled carbon nanotubes (MWNTs) as the cathode field emitters were studied. The cathode filaments were prepared by eletrolessly plating a nickel (Ni) film on the cathode made of a 304 stainless steel wire dip-coated with MWNTs. The 304 wire was dip-coated with MWNTs and nano-sized Pd catalyst in a solution, and then eletrolessly plated with Ni to form an MWNT-embedded composite film. The MWNTs embedded in Ni not only had better adhesion but also exhibited a higher FE threshold voltage, which is beneficial to our FEL system and can increase the luminous efficiency of the anode phosphor. Our results show that the FE cathode prepared by dipping three times in a solution containing 400 ppm Pd nano-catalysts and 0.2 wt.% MWNTs and then eletrolessly plating a Ni film at a deposition temperature of 60 °C, pH value of 5, and deposition time of 7 min has the best FE uniformity and efficiency. Its emission current can stay as low as 2.5 mA at a high applied voltage of 7 kV, which conforms to the high-voltage-and-low-current requirement of the P22 phosphor and can therefore maximize the luminous efficiency of our FEL. We found that the MWNT cathodes prepared by this approach are suitable for making high-efficiency FELs.
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Youh MJ, Wu HC, Lin WH, Chiu SC, Huang CF, Yu HC, Hsu JS, Li YY. A carbonyl iron/carbon fiber material for electromagnetic wave absorption. J Nanosci Nanotechnol 2011; 11:2315-2320. [PMID: 21449387 DOI: 10.1166/jnn.2011.3584] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/30/2023]
Abstract
A carbonyl iron/carbon fiber material consisting of carbon fibers grown on micrometer-sized carbonyl iron sphere, was synthesized by chemical vapor deposition using a mixture of C2H2 and H2. The hollow-core carbon fibers (outer diameter: 140 nm and inner diameter: 40 nm) were composed of well-ordered graphene layers which were almost parallel to the long axis of the fibers. A composite (2 mm thick) consisting of the carbonyl iron/carbon fibers and epoxy resin demonstrated excellent electromagnetic (EM) wave absorption. Minimum reflection losses of -36 dB (99.95% of EM wave absorption) at 7.6 GHz and -32 dB (99.92% of EM wave absorption) at 34.1 GHz were achieved. The well-dispersed and network-like carbon fibers in the resin matrix affected the dielectric loss of the EM wave while the carbonyl iron affected the magnetic loss.
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Affiliation(s)
- Meng-Jey Youh
- Department of Information Technology, Hsing Wu College, Taipei County, 244 Taiwan, ROC
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